A curing technology with active energy rays enables low-temperature curing, process reduction, short-time curing and microfabrication as compared with existing thermal curing techniques, and is widely used for adhesives, sealants, coating agents, resists and the like, making full use of the characteristics thereof. The curing method mainly used in curing with active energy rays is broadly divided into radical polymerization and cationic polymerization. A composition to be cured through radical polymerization comprises, as the main ingredients thereof, a photoradical generator and a (meth)acrylate resin, and is characterized in that it is cured immediately after irradiation with active energy rays, but has some problems in that, in general, the adhesion power thereof is low, the curing shrinkage is large and the heat resistance is poor. A composition to be cured through cationic polymerization comprises a photocation generator such as a diaryliodonium salt, a triarylsulfonium salt or the like, and a cationic polymerizing resin such as an epoxy resin, an oxetane resin, a vinyl ether resin or the like, in which the photocation generator generates acid through irradiation with active energy rays to cure the cationic polymerizing resin therein. The cationic polymerization is characterized by rapid curability, high adhesion power and low curing shrinkage, but has some problems in that there may occur curing failure owing to the moisture or some slight basic contamination of the surface of the adherend, and the adherend of a metal or an inorganic material, if used, may be corroded by the strong acid existing in the system.
As one means for solving the problems with such cationic polymerization, anionic polymerization with a photobase generator capable of generating a base through irradiation with active energy rays has become studied recently. As the photobase generator, for example, generally known are carbamate derivatives and oxime ester derivatives; and these compounds generate primary or secondary amines through irradiation with active energy rays and are used in curing of epoxy resins (Non-Patent Documents 1 to 4). The technique of generating a base with active energy rays is much used in photoresist technology. For resists, curing mode of anionic polymerization which is little troubled by termination reaction is much used, for the purpose of securing the dimensional stability of the developed edges (Non-Patent Document 5, Patent Documents 1 to 3).
However, the basic compounds to be generated by these compounds through irradiation with active energy rays are primary or secondary amines having a low degree of basicity, and are therefore insufficient for fully curing epoxy resin. As a photobase generator capable of photochemically generating tertiary amines having a larger degree of basicity, aromatic aminimide compounds have been reported (Patent Documents 4, 5); and some cases have been reported in which the thermal curing onset temperature is low after irradiation with active energy rays in addition reaction of an epoxy resin and a polythiol compound or the like.
However, these aromatic aminimide compounds require a high temperature in thermal curing therewith, and the thermal curing temperature thereof after irradiation with active energy rays is not still sufficiently low.